Human brain is NOT two separate organs

 

A terrible headline on a press release made its way through social media the other day, misleading thousands of people.

 

Human brain is two separate organs, Stanford Medicine-led research finds

By Krista Conger

September 18, 2026

A new study led by Stanford Medicine found the brain is two separate organs adjacent to one another. The finding could aid research into devastating neurological diseases.

For centuries, scientists have thought of the brain as a single, unified organ. But new research led by Stanford Medicine reveals that what we call the brain is two distinct organs that evolved independently over hundreds of millions of years.

 

Except it's not true! 

 

The senior author Dr. Kyle Loh came to the opposite conclusion, as he noted in a Nature News story:

“The brain is one organ,” says study co-author Kyle Loh, a development biologist at Stanford... “But it’s built in two different parts that connect and work together.”

 

There are two types of neural progenitor cells, which is not the same as saying “two separate organs”: 

The research suggests that one type of precursor cell forms the segment called the hindbrain, which is crucial for basic functions such as heartbeat and breathing. A second type of precursor cell, meanwhile, generates two structures: the forebrain, a central player in higher-order functions such as reasoning and planning, and the midbrain.

 

And some researchers even say “it's hard to rule out the existence of a single brain progenitor that appears only briefly and gives rise to the dual precursor...”

 

But it's too late! All the so-called news outlets that faithfully reproduce press releases have parroted the same terrible headline (e.g., The Independent, The Telegraph, Neuroscience News, New York Post, Discover Magazine, etc.). It's on reddit and slashdot [that still exists?] and LinkedIn and Bluesky. 

And now everyone believes the “two separate organs” story.

We already live in a post-truth society. why am I upset?

 

Stable Diffusion prompt: Two brains sitting at the bar with bottles labeled with neurotransmitters,  The labels:  dopamine, serotonine, acetyloholine on the bottles are clearly visible

Reference

Jokhai, R.T., Dundes, C.E., Ahsan, H.S. et al. Two parallel neural ectoderm progenitors contribute to the developing brain. Nat Neurosci (2026).